The present invention relates to a sorting arrangement according to the preamble of patent claim 1.
For sorting flat items of mail, such as letters, postcards, packets and the like, in accordance with the distribution information specified on their top surface, it is known for these items of mail to be received into special containers, transported and discharged in a controlled manner.
EP-A-0608161 thus discloses a sorting apparatus in which flat articles are transported laterally into containers from the outside by means of a channel-like, fixed-location feed apparatus. These containers, which circulate in a closed loop, are moved horizontally past the feed apparatus and by the specific opening of flaps, in accordance with the sorting instructions, the items of mail then drop into sorting containers located therebeneath. In order for the items of mail to be introduced reliably into the moving containers, either it is necessary for the items of mail to have a very high transporting speed in the feed apparatus, which may result in damage when the items of mail are braked in the container, or the speed of the containers is very low or the containers are at a standstill during the introduction operation, which means a reduction in the machine throughput.
In order to organize items in a certain order, EP 820 818 A1 has disclosed a solution which utilizes an intermediate store which comprises containers which circulate on a conveying arrangement in a conveying loop with at least two semicircular conveying sections, and can each receive an item of mail and, on command, discharge the same again into the actual depositing receptacle. In this case, initially all of the items of mail which are to be organized are accommodated in any desired sequence in the pockets of the intermediate store. Then, the items of mail are removed from the containers of the intermediate store, and transferred into the depositing receptacles, such that they are located in the latter in the order which is to be produced. The depositing receptacles, which are open at the top, are located along the rectilinear sections of the conveying arrangement beneath the containers.
In order to improve the introduction of the items of mail into the containers, the end section of the transporting means of the feed arrangement, according to WO 97/10904, has been configured pivotably such that, during the introduction of the respective item of mail, said end section is pivoted along in essentially the same direction, and at essentially the same speed, as the moving container, and is pivoted back again following the introduction operation.
If it is necessary or advantageous, during the respective sorting run, for items of mail to be loaded into empty circulating containers while other containers are still full, the feed operation has to be coordinated with the position of the empty containers, i.e., if a plurality of full containers are located between an empty container and the following empty container, the operation of feeding the items of mail is interrupted until such time as the full containers have moved past the introduction location. This stopping of the operation of feeding items of mail, however, results in an undesired loss in throughput.
A further important feature of sorting apparatuses is constituted by the dimensions thereof, which are to be as small as possible. In order to reduce the dimensions of corresponding sorting apparatuses, CH-A-267002 and JP-A 59053317 have thus described solutions in which the feed arrangement extends into the interior of the conveying loop and the articles are transported laterally into or onto the containers on the inside.
An object of the invention specified in claim 1 is thus to provide a sorting arrangement of the generic type which has at least one feed arrangement and containers which circulate in a conveying loop and are intended for laterally receiving, for transporting and for discharging in a controllable manner the items of mail to sorting depositing receptacles arranged along the conveying loop, and which has smaller dimesions and allows a higher throughput when items of mail are loaded into empty containers in a situation with already/or still full containers.
By virtue of the lateral openings of the containers, for loading purposes, being shifted, in relation to the prior art, into the interior of the conveying loop and the transporting means of the feed arrangement being arranged partially within the conveying loop such that the items of mail are transported into the lateral openings of the containers in a horizontally aligned, semicircular conveying section, it being possible for the end section of the transporting means to be pivoted about the center point of the semicircular conveying section, there is a reduction in the required dimensions of the sorting arrangement and, during pivoting of the end section of the transporting means, on account of the semicircular container arrangement, there is no need for any length compensation.
Advantageous configurations of the invention are illustrated in the subclaims.
It is thus advantageous, in addition to the known pivoting for the introduction of the items of mail into the containers, for the end section of the transporting means to be pivoted such that the item of mail which is currently to be introduced can be loaded into an empty container, without delay, within a defined pivoting region. If a plurality of full containers are thus located between the container which has just been loaded and the container which is next to be loaded, then there is no need for the item-of-mail feed speed to be reduced, or even stopped, in each case until the empty container has reached the introduction location, which up until now has always be in the same location; rather, the end location of the transporting means can be pivoted to such an extent counter to the transporting direction at such a speed that the next item of mail is introduced into the next circulating empty container with the item-of-mail feed speed maintained. Relatively high losses in throughput are avoided in this way. Once the end section has reached the end of the pivoting region, counter to the transporting direction, it obviously has to be pivoted back to the start.
In a further advantageous configuration, the containers are inclined in the transporting direction, in order that the items of mail have a defined position in the container and slide reliably into the depositing receptacles. For this purpose, the orientation of the end of the transporting stretch (introduction location) more or less corresponds to this inclination. A vertical orientation is present at the pivoting point of the transporting means, in order to allow a straightforward pivoting mechanism.
In order to ensure an unobstructed feed of items of mail and good accessibility, it is advantageous for the separating arrangement of the feed arrangement to be arranged outside the conveying loop and beneath the container plane. The transporting means then leads in an upwardly sloping manner into the interior of the conveying loop such that it terminates level with the containers.
It is also favorable for the transporting means to be configured as a sandwich belt system in which the items of mail are retained, and transported, in a state in which they are clamped in between elastic belts, as a result of which the level of gap shifting can be kept low. In order to keep the differences in length of the returning belts to a low level during pivoting, these are guided past the pivoting point as closely as possible to the same.
In a further configuration, the depositing receptacles are subdivided into two more or less equally sized groups, it being the case that, in sorting runs proceeding one after the other, the items of mail are alternately sorted only into one of the two groups. This makes it possible for the machine to be loaded and unloaded by one person without the sorting procedure being stopped.
If the items of mail are advantageously loaded into empty containers even when items of mail of the previous sorting run are still located in containers, the throughput increases.
In a space-saving development of the invention, the reading arrangement and, if required, further subassemblies, such as measuring arrangements and printers, are arranged along the fixed part of the transporting means.